Abstract: Bacteriological and molecular biological methods were used for the diagnosis of one sample of sheep from a goat farm of Guangxi in August 2020, the isolated strain by morphology, physiology, biochemistry and 16S rDNA was sequenced, and identified as Streptococcus, Pasteurella multocida positive identified by PCR amplification. Drug sensitivity analysis were perfomed on the isolated pathogenic bateria. The drug susceptibility test showed that the bacterium was highly sensitive to penicillin, enoxacin, ofloxacin, oxytetracycline, cefotifuran sodium. The pathogenicity test showed that this strain has strong pathogenicity. According to the test results, the disease is caused by the mixed infection of Streptococcus and Pasteulobacter multocida.

Key words: bacteriology, Streptococcus, Pasteurella multocida, drug sensitivity test, pathogenicity